As energy costs rise, conventional hybrid vehicles are becoming increasingly prevalent in the automotive market and provide an alternative to existing vehicles powered solely by internal combustion engines. One type of conventional hybrid vehicle, a diesel hybrid electric vehicle, employs a diesel-powered internal combustion engine that is assisted by a battery-powered electric motor. In operation, the diesel-powered internal combustion engine may recharge the battery and/or provide a driving force to such conventional hybrid vehicles. Therefore, importantly, both the diesel-powered internal combustion engine and/or the battery-powered electric motor may provide the driving force to conventional hybrid vehicles.
In contrast, a plug-in hybrid electric vehicle, also known as a range extended electric vehicle (REEV), employs a battery that may be recharged both from an external power source, such as household alternating current, or from an internal power source, such as a generator powered by an internal combustion engine. Therefore, if a driver of a plug-in hybrid electric vehicle never depletes the battery before recharging via the external power source, e.g., never travels outside a range where the battery requires recharging from the internal combustion engine, it is possible to never employ the internal combustion engine of the plug-in hybrid electric vehicle.